Mr Higgins said, "It is evidence, if there ever was evidence needed, of our commitment to the NatWest brand. That question should now have been erased because we are spending a load of money on the brand."

Royal Bank of Scotland acquired NatWest in a &#xA3;21bn deal which propelled the group to second in the list of largest UK high street banks.

Cost savings of &#xA3;1.44bn a year have already been achieved from the tie-up. The RBS scrapped NatWest's branch closure programme and put more staff into outlets.

In the last three years, NatWest's personal customer base has grown 11% while RBS's retail banking arm achieved an 8% lift in profits to &#xA3;3bn.